Leviticus 25:48-52

48after that he is sold he may be redeemed: one of his brethren may redeem him; 49or his uncle, or his uncle’s son, may redeem him, or any that is nigh of kin unto him of his family may redeem him; or if he be waxed rich, he may redeem himself. 50And he shall reckon with him that bought him from the year that he sold himself to him unto the year of jubilee: and the price of his sale shall be according unto the number of years; according to the time of a hired servant shall he be with him. 51If there be yet many years, according unto them he shall give back the price of his redemption out of the money that he was bought for. 52And if there remain but few years unto the year of jubilee, then he shall reckon with him; according unto his years shall he give back the price of his redemption.